This document outlines different aspects of performance appraisal systems including definitions, importance, processes, methods, barriers, and limitations. It discusses the purposes of performance appraisal including development, feedback, administrative decisions around salary, promotion, retention and termination. Common methods described are ranking, paired comparison, forced distribution, graphic rating scales, MBO, BARS, assessment centers, and 360-degree/multi-rater feedback. Barriers mentioned include personal bias, lack of uniform standards, and stress on the individual rather than performance.